This invention relates to bird feeders and more particularly pertains to a squirrel-proof bird feeder, which prevents a small animal such as a squirrel from gaining access to the seed in a bird feeder.
The use of squirrel-proof bird feeders is known in the prior art, and many implementations have sought to prevent squirrels and other such animals from raiding bird feeder stations. In addition to preventing bird enthusiasts from enjoying their hobby, these unwanted intrusions also cause significant monetary loss in terms of money spent on frequently replenishing bird feed.
Earlier inventions included mechanical as well as electrical devices that depend on specific features such as weight-sensitive mechanisms and trip switches. These inventions have suffered from several limitations. For example, some require special mounting structures as well as customized bird-feeder stations. Such specialized structures are cumbersome to implement and can be expensive thereby making them commercially unattractive. Other inventions while discouraging feeding, remain ineffective in dislodging the animal, thereby resulting in damages caused by the frustrated animal attacking the mechanism. Problems encountered by inventions utilizing weight sensing mechanisms include denial of feed to larger birds or when several birds alight on the feeder simultaneously. Jamming of moving parts is another issue that also renders certain mechanisms ineffective. Inventions which require electrical connections have tended to either require regular battery replacement, or cabling connections to a suitable 120V AC source that can prove cumbersome and potentially hazardous. Normal squirrel raiding behavior on a bird feeder consists of climbing up the mounting pole, hanging upside down from a suitable anchor and scooping out bird feed with its front paws. When the bird feeder is located close to taller structures such as trees, buildings or railings, the squirrel leaps on to the top of the feeder thereby bypassing certain preventive devices which may be attached at a lower level on the mount.
The present invention provides a solution that can be used on commercially available bird feeders using an effective process that resists as well as discourages squirrel raids without causing harm to the animal.
An object of the invention is to provide a cheap, effective and self-contained mechanism that can be used on most commercially available tubular bird feeders to withstand squirrel raids. This allows birds to be fed satisfactorily and consequently attracts more birds thereby leading to an enhanced bird-watching experience. Squirrels are discouraged from raiding bird feeders and revert to foraging in other places.
A further object of the invention is to provide a system that does not physically harm squirrels while in operation, and also has a lengthy product life with little or no human intervention for maintenance or servicing.
A further object of this invention is to provide a product that pays for itself quickly by reducing bird feed costs and can be manufactured easily at low cost, thereby making it attractive to the general public.
The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new squirrel-proof bird feeder apparatus and method which has many of the advantages of existing devices and incorporates many novel features that result in a new squirrel-proof bird feeder which is not anticipated, rendered obvious, suggested, or even implied by the prior art bird feeders, either alone or in any combination thereof.
To attain this, the present invention generally comprised of attachable collars that are mounted, suitably spaced, around commercially available tubular bird feeders. An electrical source, attached to the base of the bird feeder, is powered by solar cells and battery backup, and provides high voltage that is fed into copper wire loops that are built into the attachable collars. The copper wire loops also incorporate projecting barbs along the circumference of the loops. When a squirrel climbs on to the bird feeder tube and straddles two such collars, thereby bridging two copper wire connections, an electrical path is created, applying voltage to the squirrel and causing it to be dislodged from the bird feeder. The anatomy as well as behavior of birds using the feeder perches precludes similar electrical contact, as they will not be bridging two collars in the manner that a squirrel will while it travels along the length of the bird feeder tube would.
The apparatus consists of two main components: an electrical system consisting of solar panels, battery backup and electronic circuitry to generate high voltage; and a mechanical system consisting of squirrel-proofing collars, high-voltage power conduit and a housing for the electrical components.
While several types of solar panel fixtures can be utilized, one particularly convenient type consists of flexible silicon solar panels that can be wrapped around the mechanical housing for the electronics, also referred to as the Control Module. This enables the solar panels to gather sunlight and generate electricity all day long.
The batteries used are rechargeable types, which generally utilize nickel metal hydride or nickel cadmium technology. With improvements in battery technology several other options can be utilized. For example, Lithium-ion types, though handicapped by environmental heat constraints, could provide improved efficiency in energy generation. The rechargeable batteries are charged by the solar panels, and provide a source of electrical power to the electronic circuitry when the solar panels are unable to do so at night or during unfavorable solar conditions.
The electronic circuit accepts DC voltage from either the solar panels or the batteries and generates a pulsing high voltage signal with a limited current output. This kind of voltage proves sufficient to dislodge small animals from the bird feeder without causing them permanent harm. The electronic circuit incorporates low voltage to high voltage conversion, energy storage and pulse generation.
The squirrel-proofing collars encircle the tubular bird feeder and are placed in between the feeding perches as well as between the top of the feeder and the first feeding perch located below the top end of the bird feeder. The ring itself is made of non-conductive plastic, preferably re-cycled, and has a hinge 180 degrees from the ends that attach to the Main Power conduit. The hinge enables the rings to be opened, much like a solid bracelet, and placed around the circular body of the bird feeder. Bare copper wire has been wrapped around these collars in such a manner that it provides the unsuspecting squirrel a convenient object to hold on to. This mechanism is further enhanced by the provision of several protruding barbs along the periphery of the collar. These barbs have been created by suitably twisting the bare copper wire. Furthermore, the topmost collar is equipped with an additional connection to the top metal housing or bird feeder hanging wire, thereby adding these elements as part of the circuit.
The main power conduit conveys the high voltage generated in the Control Module to the multiple squirrel-proof collars. It also acts as a mechanical anchor for easy installation of the collars along the length of the bird feeder tube.
The Control Module houses the electronic circuitry and rechargeable batteries inside a waterproof enclosure and has the solar power panels mounted around its external, cylindrical surface. It incorporates several other features such as a photo-detector switch, a LED indicator and an external power coupling mechanism to allow connection to wires from the Main Power conduit.